The Digital Imaging Core (Core A) comprises valuable and modem tools, which are to be made available as[unreadable] routine services to program participants. A major goal of Core A is to provide uniform services to enable Program[unreadable] investigators to validate transduced cardiac cells and tissues. Validation includes assessing level of gene[unreadable] expression, cell-to-cell variability in expression, and structural or functional consequences to transduced cells of[unreadable] the altered gene expression. Services include 3-dimensional cell and tissue digital imaging with multi-color[unreadable] fluorescence microscopy for both living and fixed samples. Since the last review, Core A has evolved to include[unreadable] access to a multi-photon and a multi-spectral confocal microscope fitted for live-cell imaging, and an intra-vital[unreadable] confocal system for live animal imaging. Many components of this Program involve analysis of gene expression in[unreadable] cells and tissues, and as such this Core will be widely utilized. Based upon high resolution imaging techniques,[unreadable] including a DeltaVision deconvolution microscope system and UNIX workstations, these services include[unreadable] quantitative image analysis, time-lapse microscopy and volume 3-dimensional renderings of cells and tissues.[unreadable] Through Core A image analysis is greatly enhanced through interactions with the VisLab at the San Diego[unreadable] Supercomputer Center, with use of NPACI Scalable Visualization Tools. These tools allow for real-time[unreadable] exploration of the special locations of 3 or 4 cellular components in 3-D. These services have been crucial for[unreadable] individual lab projects and intra-programmatic research projects in this new program. In this service, animal[unreadable] tissues following transgene expression can be analyzed at several levels, including gross pathology and 3-[unreadable] dimensional tissue imaging with immunofluorescence staining. The service will be able to provide imaging[unreadable] analysis of various aspects of the targeted tissues, including specific cell type identification of transgene[unreadable] expression, tissue inflammatory responses, resultant tissue organization, and any changes in cellular gene[unreadable] expression or sarcomeric structural organization. Cells transduced in culture can be imaged as live cells revealing[unreadable] temporal relationships or as fixed samples, stained with immunofluorescent reagents for subsequent 3-[unreadable] dimensional structural analysis. As research goals and efforts within our Program address the molecular and[unreadable] cellular functions of endogenous and transduced genes, this resource promises to provide cost-effective support[unreadable] for these cellular, tissue and animal-based studies.